1. Field of the Invention
This invention relates to tractor implements, and particularly, to an implement for scrubbing pavement attachable rearward of the tractor on a 3-point hinge hitch.
2. Prior Art
Independently-motored street sweepers are well-known. Likewise, various plows and sweepers mountable forward of a drive vehicle are known as are sweeper attachments mounted rearward of a drive vehicle. These sweepers comprise long bristle brushes adjusted to slightly contact a street surface so as to minimize brush wear yet still impel street litter into a collection mechanism. It is unknown to have a rotating brush tractor implement removably towable behind a tractor and that has substantially nonpliable brush bristles sufficient to scrub a street or runway surface to remove materials adhering to pavement, typically of asphalt or concrete, such as tire rubber as opposed to only materials generally loose on the surface.
Thus, it is an object of the present invention to have a towable scrubber. It is a further object that the scrubber include substantially nonpliable brush bristles suitable for scrubbing rather than light sweeping. It is further object that the scrubber be towable by a category I or II tractor. It is yet another object that the scrubber be adjustable in height such that it can be lifted off the asphalt or concrete pavement surface or lowered to increase force on the brush bristles for augmented scrubbing action. It is still another object that the scrubber optionally comprise two parallel cylindrical scrub brushes acting in series.
These and other objects are achieved in a tractor pavement-scrubbing implement with a rotating transverse cylindrical brush adapted to attach to a 3-point hitch, two opposite transverse points and an elevated central point dividing the transverse points for lifting and lowering the implement. Thus, the brush may be lifted off the pavement surface or may be lowered, even pushed to the pavement surface, by the 3-point hitch. When the upper hitch point is actuated the implement is rotated forward, or clockwise, thereby lowering the brush onto the pavement surface. The brush can further be lifted or lowered to or from the pavement surface by lifting the tractor transverse points, typically hydraulically actuated hitch attachment members. Typically, the implement rides on wheels on each side of the transverse implement with the brush mounted forward of the wheels. Thus, when the hitch is lowered or lifted by the tractor 3-point hitch, the implement pivots on its rearward wheels.
The implement comprises a first rotatable cylindrical brush mounted transverse in the implement adapted to rotate counterclockwise opposite the rotation of the supporting wheels and the direction of travel for increased scrubbing action. The brush bristles are characteristically shorter than a sweeping brush having length between 2 and 3xc2xd inches on a brush 14 to 20 inches in diameter for a brush bristle to brush diameter of approximately 7 to 1. Thus, the bristles are stiffer than sweeper bristles and suitable for scrubbing. The brush bristles may be steel or stiff plastic. Together, this provides a stiff brush suitable for scrubbing as opposed to sweeping, which is commonly achieved with much longer, pliable bristles.
Optionally, a second cylindrical brush parallel and axially offset from the first is included, rotating counter to rotation of the first brush clockwise to provide opposite scrubbing action complementary to the first brush.
There is no motor on the implement, either to propel the implement or to drive the brushes. Rather, the implement is towed by the tractor and the brush is driven by a tractor power take-off drive. To increase the brush rotational speed, again to augment scrubbing action, a gearbox, or power transfer case, is installed between the tractor power take-off drive and the brush. Multiple gears allow selection of a suitable brush rotational speed. Optionally, the gear box may be dual shaft to allow each brush to be driven by an independent drive shaft.
A magnetic bar is attached transversely rearward of the housing disposed close to but spaced apart from the pavement to collect iron debris on the pavement.